The Role of Oxidative Stress in Skeletal Muscle Regeneration

The repair process of wounded tissue involves the coordinated activities of muscle precursor cells (MPCs) in response to local and systemic signals. Following tissue injury, the microenvironment, which is characterized by excessive production of reactive oxygen species (ROS), is attenuated. Here we studied the efficacy of an antioxidant, N-Acetyl-L-Cysteine (NAC), in vitro and in vivo to ameliorate the damage that results from trauma so that repair and regeneration of wounded muscle tissue is enhanced and functionality is improved. MPCs were isolated from rat tibialis anterior muscles and exposed to increasing concentrations of H2O2 in the presence or absence of NAC for the in vitro assays. MPC proliferation, differentiation, and fusion into myotubes was assessed by IncuCyte microscopy, live/dead viability assays, MTS proliferation assays, and myosin heavy chain immunohistochemistry. CellROX reagent was used to detect ROS. For in vivo assays, adult female Lewis rats were subjected to compartment syndrome injury by applying 120-140 mmHg compression for 3hrs. Half of the injured rats received NAC injected intramuscularly and the other half received equal volume of PBS at 24, 48, and 72hrs after injury. Myogenesis, angiogenesis, fibrosis, and function were determined using RT-PCR, western blot, Masson’s trichrome stain, and contractile force of the TA muscle as an isometric force (Hz), respectively. In vitro, NAC administration resulted in a decrease in oxidative stress levels that was associated with significant survival benefit during oxidative damage. When used in vivo, NAC administration also showed decrease in tissue fibrosis, increase in myogenesis, angiogenesis and muscle function. These results suggest that treatment of skeletal muscle injuries with antioxidants may be a viable option for the prevention of long-term fibrosis and scar formation and improvement of recovery of muscle function.

Grantor dc:publisher

Wake Forest University

Year dc:date.issued

2018

Author dc:creator

• Yoseph, Benyam Petros

• Fibrosis

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10339/92383

OAI identifier oai:identifier

oai:wakespace.lib.wfu.edu:10339/92383